What is the angular momentem of an electron in Bohr's hydrogen atom whose energy is `- 3.5eV`?

Options

A. `(h)/(pi)`
B. `(h)/(2pi)`
C. `2(h)/(pi)`
D. `(h)/(3pi)`

Answer

A

Explanation

First, we need to identify the quantum number of the energy level.
As `E = - (13.6)/(n^(2))`, we have
`- 3.4 = - (13.6)/(n^(2)) or n = 2`
The angular momentum quantuzation gives `L = mvr = (nh)/(2pi)`
Subsitituting `n = 2` , we get `L = (2 h)/(2pi) = (h)/(pi)`